For a company that aims to excel in making information and products clean and easy to use - and one with an eye on consumer electronic devices for lucrative markets - it makes absolute sense that Apple should exploit the trend for fitness and health data with Health, its new app.

Apple insisted from the first mention of its new data app Health on Monday that users' privacy will be protected. But with a rapidly growing industry built around aggregating and organising health data, how far and wide is our health data being shared?

Like many people, I’m more into the principle of fitness than the practice. I’m don't go to a gym, climb mountains or ride bikes down them, and am as far from early morning runners as its possible to be. I’d have my breakfast in bed, if I trusted anyone else to make a decent coffee.

But I also like gadgets, so Fitbit's activity tracker - the slick, sliver of a device called the One - motivated me to start exercising and I've been using one ever since.

My first device was run over by a car (I wasn't wearing it at the time) and Fitbit replaced it free of charge. I've worn it daily ever since.

Until today.

Before the break up, we’d had happy times. The experience of having technology as an integral part of your day, as part of your body, can be enlightening - a constant stream of information that reflects your behaviour and reports on your state of health. When you analyse this realtime feedback, you can't help but adjust your activity and, in a way, your behaviour.

I never felt bullied by my Fitbit. It was more a gentle coercion to do a little bit more of what was good for me so that I'd reach my daily exercise goal, and keep up with the handful of others with whom I share my data.

Or rather I thought it was only a handful of others. But it seems that data is being spread far wider than we thought. In reality it seems we are losing control over some of our most intimate data, handing over details of every heartbeat we have and minute we sleep.

Apple may well leap ahead in this market, but at the moment FitBit is exploiting its lead. Sharing health data with third parties is potentially lucrative; think of the targeted drug adverts, health food drinks, low-carb low-calorie drinks and the rest. Imagine the life insurance salesmen either beating down your door or blocking your calls if the data says you look like a bad risk.

Who is aggregating your health data - and at what cost?

We should have seen this coming - it's pretty obvious that if you are aggregating data into a server you don't own, someone will think to make use of it. This happens all the time - it can even be useful to both company and customer - and it would be foolish of any firm, FitBit included, not to consider the value of this data in their business model. But at what cost to the individual?

Early 2012 when I signed up to Fitbit, I paused to think about where my data was going, how it might be used, and couldn't think of a reason not to let them have my seemingly innocuous step data.

Fitbit's privacy statement is more than 3,000 words long and regularly updated. It's reasonably open about what they will do with your health data, for those who bother to read it. (Anyone out there have their solicitor give those documents the once over? Me neither).

But I am no longer happy to share what they want me to share.

So, what if, like me, you don’t feel comfortable with Apple or FitBit’s vision of health data collection? What are the alternatives?

New brands and devices surface regularly, but three of the best looking devices are Jawbone, Shine and Garmin.

How much to access health data? Garmin's API access costs $5,000

Garmin offers some interesting data-export options that would allow me to use my health data in useful ways, but there are worrying limitations in their Application Programming Interface (API), the window that specifies how programs talk to one another.

In the Garmin’s case, the major limitation seems to be that the API is no longer free to access. It's bad enough that APIs usually offer access to a limited amount of data, but Garmin now ransoms it out at $5,000 a go.

This means small software developers and coders who might want to design an app, or even someone who wants to get a complete dataset into a spreadsheet, have to pay through the nose for the right to do so. That’s hardly accessible to the not-for-profits and passionate bedroom coders who do some of the most interesting and innovative work in this brave new data rich world.

This cuts right to the heart of the issue of data collection and data sharing. Why would I want my personal health data to be collected, shared, turned into profits by a company that will not also allow me to use that same data because it limits access to its API, that critical information bridge?

Am I happy to collect information from the very heart of myself, and then not be able to use it as I want? For this data to be accessible only for wealthy corporate use?

No, I’m not. They’re my vital signs, my vital statistics and I should be able to do with them what I want, not sign the rights to them over to someone else.

The importance of the magical APIs and getting them right is hard to overstate; it’s partly about about taking data and making it genuinely useable, or "rich", rather than just spewing out raw data and numbers - in the case of activity monitors, heart rate and distance traveled and so on.

And it’s partly about tailoring use of data, so I can choose what apps and systems I share my information with, rather than giving one firm a monopoly over where my vital statistics are sent and analysed.

An open source alternative

Fluxstream is an open-source, non-profit organisation which deals with personal data, including the sort of health-related information collected by the likes of FitBit and Garmin.

Candide Kemmler and Anne Wright, Fluxstream’s founders, make a persuasive case for having open and accessible APIs.

"Our take is that people should be able to use their data freely and that a good syncing API is the best way to enable that. Data export is simply not enough,” said Kemmler.

The basic requirements are a few data points, and the ability to transfer them is all it takes.

“These simple requirements are very often not met and one has to go through a whole lot of hoops and loops to achieve the desired result."

Is charging for health data sustainable?

Companies don’t always want to give something away when they can sell it -even if it enhances user experience and ultimately makes their product more desirable.

In the short term, selling APIs can make a firm more money. Long term, they’re more likely to make a product obsolete by limiting its horizons.

The sooner these device manufacturers realise we want, and have a right to, full access to the data we use their machines to aggregate, the sooner we can curate it how and where we want.

Networked devices need to connect and share freely, and Apple, Fitbit or Garmin must acknowledge that. It will make these services for more compelling when they do, so that we can freely export, sync and analyse the data their devices allow us to compile.

These data steams show the intimate workings of our bodies, our lives. It's not just the "internet of things" they are building technology for. It's an internet of people.